the 22-foot high catch fence at the impact point had been replaced. by all accounts, if not for the fence, the accident might have been catastrophic. >> it kept the car on the racetrack. the parts and pieces fly into the stands, yes, they did. but the catch fence is to keep the majority of the car on the racetrack and out of the grandstands. so it did a fantastic job. >> reporter: still, there were injuries. some serious. some victims still hospitalized. nascar will, experts say, go back and look at the crash second by second, piece by piece, a quick fix, perhaps raise the protective fence, move fans further away from the track. but that would impact one of the attractions of auto racing, how close fans can get to the action. someti sometimes, it's just too close. now, next week, there's a race in arizona and nascar officials say they have been in touch with track officials in phoenix and they are sharing what they know at this point about how the accident here happened on saturday. wolf. >> john zarrella from daytona beach, thanks very much. >>> osca